Modeling of aging processes in the insertion compounds

The aging phenomena occurring in the course of cycling processes in the insertion host-guest compounds are discussed in the framework of a simple model. It takes into account two types of effects. One can be attributed to modifications of the host/guest solution interface in a form of an effective energetic barrier. The other is associated with the host matrix disordering that is translated into a change in the distribution of the host site energies as a function of the applied potential or the concentration of the guest species. It is found that the aging properties depend on the preparation mode, the cycling conditions and the insertion induced transformations. The impact of these transformations on the aging is determined by the matrix sensibility.